No trick here, that image is moving. Look at the hair if you can pry your eyes away from the main attraction. I think this is a GIF
What hair? But you might be right this could be a GIF
Should this already be toggled NSFW in your opinion? or only pure nudity or only pure pornografy or all kinds of gore?
NSFW, like beauty, is in the eye of the beholder. Most employers don't want the employees surfing the internet on the company dime and all have some policy about objectionable content. So what I think is SFW may well not be for someone else and I think it is better to warn worktime surfers and then it is their choice. So good call on your part.